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Study question Does enhancing oxygen availability during dynamic in vitro culture of bovine ovarian cortical tissue (BOCT) improve follicle growth and health? Summary answer Enhancing oxygen availability during dynamic in vitro culture of BOCT in perifusion bioreactors (PB) does improve follicle health and yield to secondary follicles What is known already Oxygen availability has been demonstrated to represent a key factor in follicle health and growth during in vitro culture of bovine and human ovarian cortical tissue (HOCT) under static culture conditions. Disruption of solutes gradients and application of physiological fluid mechanical stress, through in vitro dynamic culture of HOCT in a newly designed perifusion bioreactor have been shown to further enhance follicle growth and health. As it shows striking similarities with human, bovine folliculogenesis is considered a valuable model to study follicle growth in vitro Study design, size, duration Bovine ovaries from animals aged 8-24 months were collected at slaughterhouse. In each experiment (n = 3), BOCT strips from the same ovary were cultured for 6 days in perifusion bioreactors (PB, dynamic culture) and conventional dishes (CD, static culture). Culture outcome in static culture was analysed and compared to two bioreactor configurations in which medium oxygenation was kept low by using a standard tube reservoir (StPB) or was enhanced by using a gas-permeable dish reservoir (PB+O2). Participants/materials, setting, methods Slices of BOCT 0.5mm thick were cut with a tissue slicer and chopped into 1x1mm strips. In each experiment, fresh (D0) and cultured tissue (groups of ten strips) were analyzed. Follicle stages and health were assessed by histology (hematoxylin-eosin staining). Follicle viability was estimated by labelling with live-dead far-red and propidium iodide followed by clearing before analysis at the confocal laser scanning microscope. Main results and the role of chance Overall, 2417 follicles were analyzed (histology, 1476; viability, 941). At day 0 most follicles were primordial (primordial, 88.7%; primary, 10.6%; secondary, 0.7%), and had good quality (grade 1-2, 92.2%; grade 3, 7.8%), and high viability (91.8%). At day 6, follicle growth and health in StPB was superior than in CD (StPB vs CD - staging: primordial, 6.8 vs 16.3, P Limitations, reasons for caution Although the bovine is considered a reliable model for human folliculogenesis, the study should be validated on human ovarian tissue. Wider implications of the findings A limiting step in the in vitro production of mature oocytes starting from primordial follicles is the low yield of secondary follicles after organ culture. The adoption of a newly designed dynamic bioreactor and modulation of oxygen availability could represent a valuable tool for multistep in vitro folliculogenesis. Trial registration number none

Study question Do tissue thickness and FSH supplementation affect follicle growth and health in the vitro culture of bovine ovarian cortical strips (BOCS) in gas-permeable dishes? Summary answer Culture of 0.5mm thin BOCS with 5ng/ml FSH does improve follicle health and yield to secondary follicles compared with 1mm thick BOCS What is known already Oxygen availability inside tissue has been demonstrated to represent a key factor in follicle health and growth during in vitro culture of bovine and human ovarian cortical strips (HOCS). Although, strip thickness can limit nutrients and gases diffusion in and out of the innermost tissue zone, the presence of the outer medulla in thick strips could positively affect follicle growth. The role of FSH on the progression of primordial to secondary follicles in ovarian organ culture is still debated. Study design, size, duration Bovine ovaries from animals aged 8-24 months were collected at a slaughterhouse. In each experiment (n = 3), BOCS of varying thickness collected from the same ovary were cultured with or without FSH in gas-permeable dishes for 10 and 15 days. Participants/materials, setting, methods Slices either 0.5mm or 1mm thick were cut with a tissue-slicer and were chopped into 1x1mm2 strips. BOCS were cultured for 10 or 15 days at the same tissue/medium volume ratio (groups of either five 1mm strips or ten 0.5mm strips in 5ml medium) with 0, 1, or 5ng/ml FSH. Follicle stages were assessed by histology. Follicle viability was estimated by labeling with live-dead far red and propidium iodide at the confocal laser scanning microscope. Main results and the role of chance Overall, 2314 follicles were analyzed (histology, 998; viability, 1316). At day 0 most follicles were primordial (primordial, 89.4%; primary, 8.7%; secondary, 1.9%), and had a high viability (94.69%). The best follicle growth and viability was observed in 0.5mm thin BOCS cultured with 5ng/ml FSH. In particular, when compared to 1mm thick BOCS cultured with 5ng/ml FSH, 0.5mm thin BOCS cultured with 5ng/ml FSH showed a higher and significant proportion of secondary follicles at day 10 (0.5 vs 1mm, % secondary follicles: 26.5 vs 10, P These results demonstrate that smaller BOCS thickness and 5ng/ml FSH supplementation significantly improve the growth and health of secondary follicles. Limitations, reasons for caution Although the bovine is considered a reliable model for human folliculogenesis, the study should be validated on human ovarian tissue. Wider implications of the findings A limiting step in the production of mature oocytes starting from primordial follicles is the low yield to secondary follicles at the end of organ culture. Given the similarities between bovine and human folliculogenesis, the best culture conditions herein identified could contribute to the refinement of human in vitro folliculogenesis. Trial registration number Not applicable

The ambulatory monitoring of human movement can provide valuable information regarding the degree of functional ability and general level of activity of individuals. Since walking is a basic everyday movement, automatic step detection or step counting is very important in developing ambulatory monitoring systems. This paper is concerned with the development and the preliminary validation of a step counter (SC) designed to operate also in conditions of slow and intermittent ambulation. The SC was based on processing the accelerometer data measured by a Gear 2 smartwatch running a custom wearable app, named ADAM. A data set of eight users, for a total of 80 trials, was used to tune ADAM. Finally, ADAM was compared with two different commercial SCs: the native SC running on the Gear 2 smart watch and a waist-worn SC, the Geonaute ONSTEP 400. A second data set of eight additional users for a total of 80 trials was used for the assessment study. The three SCs performed quite similarly in conditions of normal walking over long paths (1%-3% of mean absolute relative error); ADAM outperformed the two other SCs in conditions of slow and intermittent ambulation; the error incurred by ADAM was limited to 5%, which is significantly lower than errors of 20%-30% incurred by the two other SCs.

Falls are one of the most common causes of accidental injury: approximately, 37.3 million falls requiring medical intervention occur each year. Fall-related injuries may cause disabilities, and in some extreme cases, premature death among older adults, which has a significant impact on health and social care services. In recent years, information and communication technologies (ICT) have helped enhance the autonomy and quality of life of elderly people, and significantly reduced the costs associated with elderly care. We designed and developed an integrated fall detection and prevention ICT service for elderly people, which was based on two wearable smart sensors, called, respectively, WIMU fall detector and WIMU data-logger (Wearable Inertial Measurement Unit, WIMU), their goal was either to detect falls and promptly react in case of fall events, or to quantify fall risk instrumentally. The WIMU fall detector is intended to be worn at the waist level for use during activities of daily living, the WIMU logger is intended for the quantitative assessment of tested individuals during the execution of clinical tests. Both devices provide their service in conjunction with an Android mobile device. The ICT service was developed and tested within the European project I-DONT-FALL (Integrated prevention and Detection sOlutioNs Tailored to the population and risk factors associated with FALLs, funded by EU, action EU CIP-ICT-PSP-2011-5: GA #CIP-297225). Sensor description and preliminary testing results are provided in this paper.

A sensor fusion method was developed for vertical channel stabilization by fusing inertial measurements from an Inertial Measurement Unit (IMU) and pressure altitude measurements from a barometric altimeter integrated in the same device (baro-IMU). An Extended Kalman Filter (EKF) estimated the quaternion from the sensor frame to the navigation frame; the sensed specific force was rotated into the navigation frame and compensated for gravity, yielding the vertical linear acceleration; finally, a complementary filter driven by the vertical linear acceleration and the measured pressure altitude produced estimates of height and vertical velocity. A method was also developed to condition the measured pressure altitude using a whitening filter, which helped to remove the short-term correlation due to environment-dependent pressure changes from raw pressure altitude. The sensor fusion method was implemented to work on-line using data from a wireless baro-IMU and tested for the capability of tracking low-frequency small-amplitude vertical human-like motions that can be critical for stand-alone inertial sensor measurements. Validation tests were performed in different experimental conditions, namely no motion, free-fall motion, forced circular motion and squatting. Accurate on-line tracking of height and vertical velocity was achieved, giving confidence to the use of the sensor fusion method for tracking typical vertical human motions: velocity Root Mean Square Error (RMSE) was in the range 0.04-0.24 m/s; height RMSE was in the range 5-68 cm, with statistically significant performance gains when the whitening filter was used by the sensor fusion method to track relatively high-frequency vertical motions.

The question whether barometric altimeters can be applied to accurately track human motions is still debated, since their measurement performance are rather poor due to either coarse resolution or drifting behavior problems. As a step toward accurate short-time tracking of changes in height (up to few minutes), we develop a stochastic model that attempts to capture some statistical properties of the barometric altimeter noise. The barometric altimeter noise is decomposed in three components with different physical origin and properties: a deterministic time-varying mean, mainly correlated with global environment changes, and a first-order Gauss-Markov (GM) random process, mainly accounting for short-term, local environment changes, the effects of which are prominent, respectively, for long-time and short-time motion tracking; an uncorrelated random process, mainly due to wideband electronic noise, including quantization noise. Autoregressive-moving average (ARMA) system identification techniques are used to capture the correlation structure of the piecewise stationary GM component, and to estimate its standard deviation, together with the standard deviation of the uncorrelated component. M-point moving average filters used alone or in combination with whitening filters learnt from ARMA model parameters are further tested in few dynamic motion experiments and discussed for their capability of short-time tracking small-amplitude, low-frequency motions.

The ambulatory monitoring of human movement can provide valuable information regarding the degree of functional ability and general level of activity of individuals. Since walking is a basic every day movement and an important element to introduce into one's daily routine, automatic step detection or step counting is very important in developing ambulatory monitoring systems. This paper is concerned with the development and the preliminary validation of a step counter (SC) that is especially designed for conditions of slow and intermittent ambulation. The SC was based on processing the accelerometer data measured by a Gear 2 smartwatch using a custom wearable app, named ADAM, running on the Gear 2. A dataset of 8 users, for a total of 80 trials, was used to tune ADAM. Finally, ADAM was compared with the native SC running in the Gear 2 smartwatch, and with the SC implemented in a waist-worn pedometer (Geonaute ONSTEP 400) (dataset of 8 users, for a total of 80 trials). The three SCs performed quite similarly in conditions of normal walking over long paths (1--3% of mean absolute relative error); ADAM outperformed the two other SCs in conditions of slow and intermittent ambulation; the error incurred by ADAM was limited to 5%, significantly lower than errors of 20--30% incurred by the two other SCs.

Vestibular disorders can cause severe problems including spatial disorientation, imbalance, nausea, visual blurring, and even cognitive deficits. The CLONS project is developing a closed-loop, sensory neural prosthesis to alleviate these symptoms [1]. In this article, we outline the different components necessary to develop this prosthetic. A short version of this work was presented in the NEUREL 2010 [1]. Conceptually, the prosthesis restores vestibular information based on inertial sensors rigidly affixed to the user. These sensors provide information about rotational velocity of the head; the prosthetic then transfers the information to the vestibular nerve via electrical stimulation. Here we present a project overview, development details, and summarize our progress in animal models and selected human volunteers.

This paper investigates a fall detection system based on the integration of an inertial measurement unit with a barometric altimeter (BIMU). The vertical motion of the body part the BIMU was attached to was monitored on-line using a method that delivered drift-free estimates of the vertical velocity and estimates of the height change from the floor. The experimental study included activities of daily living of seven types and falls of five types, simulated by a cohort of 25 young healthy adults. The downward vertical velocity was thresholded at 1.38 m/s, yielding 80% sensitivity (SE), 100% specificity (SP) and a mean prior-to-impact time of 157 ms (range 40–300 ms). The soft falls, i.e., those with downward vertical velocity above 0.55 m/s and below 1.38 m/s were analyzed post-impact. Six fall detection methods, tuned to achieve 100% SE, were considered to include features of impact, change of posture and height, singularly or in association with one another. No single feature allowed for 100% SP. The detection accuracy marginally improved when the height change was considered in association with either the impact or the change of posture; the post-impact fall detection method that analyzed the impact and the change of posture together achieved 100% SP.

Researchers have succeeded in partly restoring damaged vestibular functionality in several animal models. Recently, acute interventions have also been demonstrated in human patients. Our previous work on a vestibular implant for humans used predefined stimulation patterns; here we present a research tool that facilitates motion-modulated stimulation. This requires a system that can process gyroscope measurements and send stimulation parameters to a hybrid vestibular-cochlear implant in real-time. To match natural vestibular latencies, the time from sensor input to stimulation output should not exceed 6.5 ms. We describe a system based on National Instrument's CompactRIO platform that can meet this requirement and also offers floating point precision for advanced transfer functions. It is designed for acute clinical interventions, and is sufficiently powerful and flexible to serve as a development platform for evaluating prosthetic control strategies. Amplitude and pulse frequency modulation to predetermined functions or sensor inputs have been validated. The system has been connected to human patients, who each have received a modified MED-EL cochlear implant for vestibular stimulation, and patient tests are ongoing.

In this paper, we present an approach to the online implementation of a gait event detector based on machine learning algorithms. Gait events were detected using a uniaxial gyro that measured the foot instep angular velocity in the sagittal plane to feed a four-state left-right hidden Markov model (HMM). The short-time Viterbi algorithm was used to overcome the limitation of the standard Viterbi algorithm, which does not allow the online decoding of hidden state sequences. Supervised learning of the HMM structure and validation with the leave-one-subject-out validation method were performed using treadmill gait reference data from an optical motion capture system. The four gait events were foot strike, flat foot (FF), heel off (HO), and toe off. The accuracy ranged, on average, from 45 ms (early detection, FF) to 35 ms (late detection, HO); the latency of detection was less than 100 ms for all gait events but the HO, where the probability that it was greater than 100 ms was 25%. Overground walking tests of the HMM-based gait event detector were also successfully performed.

The vestibular system detects rotational velocity and linear acceleration of the head in order to identify body’s spatial orientation. Impairments of these organs induce the subject to spatial disorientation, postural instability, self-motion perception deficits, and chronic disequilibrium. Gaze stabilization performances are usually evaluated by the assessment of the Visual Acuity during head movements. This work introduces a new testing device, named Up-Down Chair (UDC), able to generate full body linear accelerations in the vertical direction. These stimuli can be tuned to mimic those encountered during natural activities. This platform has been designed to serve as an experimental set up to quantify vestibular functions and their relationship to clinical scales. Moreover, the UDC could be used to assess specific testing performance for a vestibular neuroprosthesis.

This study introduces three new robotic platforms aimed at investigating the performance of subjects affected by vestibular diseases while providing i) balance perturbations in horizontal directions while subjects carry out daily motor tasks (SENLY), ii) pure linear vestibular system stimuli in vertical direction (Up-Down Chair) and iii) pure rotational vestibular system stimuli in roll, pitch and yaw directions (Oscillating Chair).

The applicability of dissolved air flotation (DAF) treatment to fish filleting wastewater from the harbour of Mar del Plata was evaluated. The experiments were planned by factorial design, the variables were pressure, coagulant and recycle, each at two levels (23 factorial design). The responses measured were the reduction in chemical oxygen demand (COD), reduction in total solids and reduction in protein content. The results indicate that the three factors significantly influence the performance of the treatment and that there exists a high degree of interaction between the factors studied. Within the experimental conditions investigated, reductions of chemical oxygen demand (up to 74%), of total solids (up to 62%) and protein fish scales as flotation aids are shown, measuring the reduction in total solids.

Transverse intrafascicular multichannel electrodes (TIMEs) are polyimide-based microelectrodes, which are potentially very interesting to restore sensorimotor functions in disabled people. By means of microstimulation of the nerve stump of an amputee, it can be possible to manipulate the phantom limb sensation, to provide sensory feedback to upper limb amputees, and to investigate methods of treatment of phantom limb pain. The current insertion procedure of TIMEs is completely done by hand. This makes the task difficult. This paper presents the preliminary results related to the development of a robotic tool to increase the accuracy in electrode placement and reduced size of the working area. The possibility to manage insertion parameters such as force, velocity, and positioning, could decrease the risk of damaging the nervous tissue, improving the coordination, and making placements repeatable. With the aim of solving the issues avbove, we developed a first prototype of a 4DoF multi-axis device. Additional strategies concerning system components and control are discussed. We performed characterization of implantation mechanics to derive mechanical design specifications for the robotic device. Force caracterization of the pig peripheral nerve during penetration of the needle at three velocities (1, 30, 40mm/sec) was executed. Results shown inverse relationship between maximal force and velocities values. The force values extracted varied between 0.081–0.174 N.

The 'stem cell burden' hypothesis represents a plausible explanation for the association between birth-weight and the risk of breast cancer in adulthood. The size of the overall stem cell pool would be expected to affect organ size and consequently birth-weight, making birth-weight a proxy for the overall number of fetal stem cells. As stem cells are self-renewing, the greater their number is at birth, the higher will be the chance that one of them will undergo carcinogenesis over the years. To investigate the correlation between birth-weight and stem cell burden, we examined the cord blood hematopoietic CD34+ stem cell population as an indicator of the overall fetal stem cell number. We measured both the CD34+ level (by flow cytometry) and the CD34+ proliferative potential (by the GM-CFU culture), in a sample of 1037 healthy newborn cord blood donors. We found that heavier babies had a significantly greater CD34+ stem cell concentration (p0.001) and a higher GM-CFU number than lighter babies (p0.001). Thus, a high birth-weight was positively associated with a high concentration of CD34+ stem cells and also with a qualitatively higher "stemness" of this pool. Therefore, our data support the theory that birth-weight reflects the number of fetal stem cells.

A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of Brazilian Amazon and Cerrado regions over the period 2000–2002. The NASA-CASA (Carnegie Ames Stanford Approach) model estimates of annual forest production were used as the basis to generate a prediction for the standing pool of carbon in above-ground biomass (AGB; g C m−2) for forested areas of the Brazilian Amazon region. Plot-level measurements of the residence time of carbon in wood in Amazon forest from Malhi et al. (2006) were interpolated by inverse distance weighting algorithms and used with CASA to generate a new regional map of AGB. Data from the Brazilian PRODES (Estimativa do Desflorestamento da Amazônia) project were used to map deforested areas. Results show that net primary production (NPP) sinks for carbon are highest across the eastern and northern Amazon areas, whereas deforestation sources of CO2 flux from decomposition of residual woody debris are more rapid and less seasonal in the central Amazon than in the eastern and southern areas. Increased woody debris from past deforestation events was predicted to alter the net ecosystem carbon balance of the Amazon region to generate annual CO2 source fluxes at least two times higher than previously predicted by CASA modeling studies. Variations in climate, land cover, and forest burning were predicted to release carbon at rates of 0.5 to 1 Pg C yr−1 from the Brazilian Amazon. When direct carbon emissions from forest burning of between 0.2 and 0.6−1 in the Legal Amazon are overlooked in regional budgets, the year-to-year variations in this net biome flux may appear to be large, whereas our model results implies net biome fluxes had actually been relatively consistent from year to year during the period 2000–2002.

Although many patients with obstructive sleep apnea syndrome (OSAS) form part of the work force, the impact of OSAS on occupational accidents and on work performance is unclear. To address this issue, we investigated 100 referents workers without OSAS (50 blue-collar and 50 white-collar) and 331 workers affected by OSAS (144 blue-collar and 187 white-collar). Workers affected by OSAS had been involved in occupational accidents more often than referents (27.2% vs. 20%). The mean number of accidents/year was slightly higher in blue-collar workers with OSAS and significantly higher (p=0.013) in white-collar workers with OSAS than referents. Furthermore, workers with OSAS referred more impairments in work performance as difficulties in memory (p=0.000), vigilance (p=0.000), concentration (p=0.000), performing monotonous tasks (p=0.000), responsiveness (p=0.000), learning new tasks (0.006) and manual ability (p=0.023), with the mean number of impairments being higher (p=0.000) in workers with a more severe OSAS (referents = 0.32; mild OSAS = 1.11; severe OSAS = 1.70). These results suggest OSAS increases the risk of occupational accidents and impaired work performance. Given the impact of OSAS on fitness for duty assessment, occupational physicians should be aware of it and could play a strategic role in its diagnosis, in monitoring treatment, and in providing appropriate information.

The chapter describes a teleoperation system for assisting disabled and elderly people in their lives and work environments. The developed system ASIBOT (assistive robot) is part of the EU 5th FP project MATS (IST 2001-32080). The goal of the project is to come up with a new concept in teleoperated robotics systems that would help people in their daily domestic activities such as eating, drinking, shaving, grooming or simply retrieving objects from shelves or from the floor, etc. The best feature of the ASIBOT system is represented by a snake-like robot arm that is capable of moving around serially from a wall-mounted or table- mounted docking stations. The robot is also able to “jump” to or from a wheelchair. One of the important properties of proprio and teleoperation of assistive robots is the fact that the operator could be at the same time the patient, the user or the target of the task. Due to disability, the operator has limited capability on controlling the master and also considerable delays in closing the teleoperation loop. Depending on the level of the operators disability, different types of HMI are needed to be used. Some HMI are commanded by voice, simple switches or a joystick.

In this paper, we develop a system for which applications in the field of personal navigation are planned. In the current version, the system embodies a Global Positioning System (GPS) receiver and an inertial measurement unit (IMU), composed of two dual-axis accelerometers and one single-axis gyro. The IMU is positioned at a subject's foot instep, and it is intended to produce estimates of some gait parameters, including stride length, stride time, and walking speed. Data from GPS and IMU are managed by a DSP-based control box. The computations performed by the DSP processor allow to detect subsequent foot contacts by a threshold-based method applied to gyro signal, and to reconstruct the trajectory of the foot instep by numerical strapdown integration. Features of human walking dynamics are incorporated in the algorithm to enhance the estimation accuracy against errors due to sensor noise and integration drift. All computations are performed by the DSP processor in real-time conditions. The foot sensor performance is assessed during outdoor level walking trials. The traveled distance estimated by inertial dead-reckoning is compared with the estimate produced by GPS in experimental conditions where GPS can be used as a reference source for accurate absolute positioning. Results show the remarkable accuracy achieved by foot inertial sensing.

This paper reviews a new approach in the area of rehabilitation robotics. The service robot MATS helps disable and elderly people in their day life activities in common living environment like kitchen, bathroom, bedroom, etc. In this way the quality of life of the important part of population improves toward their social integration. This new prototype has new abilities like climb from one wall to another or from the table to the wheelchair, and at the same time to be attached and move with the wheelchair. The robot is totally autonomous and needs only power supply to be operated. This paper presents the distributed software architecture and the concept design of the HMI which handles the robotic system.

In this paper we illustrate the main features of a vision-based 2D localisation system, endowed with the real-time capability of estimating the location of active light-emitting markers disposed on a horizontal plane. The vision-based system revolves around using an inexpensive, off-the-shelf web-camera under computer control: the system is simple to install and operate, yet accurate to a level which is acceptable in a range of applications. Specifically, we describe how we intend to exploit the localisation system in an application whose ultimate goal is to support motor-impaired users in the approach to a specific configuration with their mobility aid, e.g., an electric wheelchair. To serve this application, the vision-based localisation system is integrated in a human-machine-interface, built around an handheld PC, which aims at providing the driver with a "top-view" representation of the scene. In our preliminary experiments, the perceptual enhancement is shown beneficial in increasing the docking accuracy up to few millimeters and tenths of degrees from the "target" configuration.

In this paper we describe a motorised rollator which aims at supporting people with motor impairments while walking and transporting objects. The prototype presented here incorporates a few additional functions, including the force enhancement to the user in the direct control mode, and the ability to follow the user at a distance, with or without collision avoidance, in the follow-me mode. The user input device for the direct control mode is composed of bilateral grips, equipped with strain gage force sensors, whose output signals are used for motor speed control. The follow-me mode is built around a trilateration system based on ultrasonic and infrared sensing technologies; the system activates a user-worn transponder for person tracking. We discuss both the motivations behind the control modes of interest and the technical solutions we have devised for their implementation. The results of some preliminary experiments are also presented and discussed, to show the feasibility of the approach.

The authors describe the notion of a distributed robotic system (DRS) based on instinctive response and cooperation. Two specific aspects of the DRS are investigated in some detail: the self-configuration capabilities and the pattern generation problem. Simulation was used as a tool for dealing with the variety of possible distributions of the DRS, of environmental conditions, and of individual reactions of each robotic unit. Problems associated with communication between robotic units are also addressed. Simulation results demonstrate that communication and cooperation are very effective in enhancing the performance of the DRS during tasks requiring exploration, such as the search for pollutants. >

In this paper, we present bird's-eye (BE) viewer - a sensor-based navigation system intended to assist motor-impaired people driving their mobility aids to a specified goal. The BE-viewer is built around a vision-based 2D localization system based on a monocular image system composed of one web-camera, and endowed with real-time capability of estimating the location of active light-emitting markers. The 2D localization system is integrated in a human-machine-interface, which provides the user with a "top-view" sketch of the current and desired configurations. We introduce a protocol for the functional assessment of the docking procedure, here interpreted as a pursuit tracking task. The protocol allows to characterize how subjects use their resources to achieve a balance between speed, accuracy and control effort, depending on whether the perceptual enhancement by the BE-viewer is available or not. The benefits of the BE-view approach are presented and discussed on preliminary experiments where normal subjects perform docking procedures using a motorized anterior walker.

The problem of developing a sensing system for robots moving in a partially or completely unknown environment is investigated. A model of a generalized sensitive skin based on different types of sensors to be located on the whole surface of a robot is illustrated. A logic and hardware structure of the low-level layer of the skin is proposed to guarantee modularity and consistency of sensory data. A configuration including ultrasonic and infrared proximity sensors was chosen for the implementation of a prototype of the skin. A possible physical layout for obtaining a conformable skin to be used on any kind of robot surface is also presented. Local and general rules for low-level sensory data fusion are defined, and possible improvements of real-time obstacle avoidance path planning strategies are discussed by introducing sensor-based instinctive behaviors. A simulation of a modified potential field-based real-time planner for a mobile robot operating in a partially unknown environments is discussed to demonstrate the feasibility of this approach.

A description is presented of the social organization of societies of cellular mobile units featuring instinctive behavior. Each robotic unit has its own personality and lives independently from the others. Useful tasks are carried out through collaboration rather than by individual effort. The behavior of each unit derives from a subsumption-like control structure, which emphasizes the roles of innate personality, external stimuli, and communication. A number of different robotic personalities are described and techniques of implementing them in real robot units are outlined. The implementation of instinctive behavior is described for the case of a robotic vehicle system (ROBBIE). >

Presents an approach to the implementation of the concept of 'distributed robotic system' (DRS), based on the notions of 'instinctive' response and cooperation. The proposed DRS is composed of cellular robotic units which operate in a constrained unstructured environment and are dedicated to environmental monitoring. This specific application, of potentially wide practical interest, poses a number of constraints to the control of the DRS, which can be solved efficiently by using the proposed approach. >

In this paper, the authors describe a sensing method, called differential compassing, which can be applied to pursue leader/follower behaviors in the field of service robotics. Differential compassing is applied to integrate proximity/range sensing in robot systems, the operation of which can involve a hands-free interaction mode, where the robot (the follower) reacts to the movements of a walking user (the leader), so as to maintain close proximity to him. Differential compassing exploits two compasses, one of them on the leader and the other one on the follower. The simple idea behind this approach is that, if a magnetic disturbance affect the two compasses, one compass will be more influenced than the other, but heading errors may have similar magnitude

To clarify the risk factors contributing to postoperative complications in elderly patients undergoing total gastrectomy, 84 patients with primary gastric cancer were evaluated. Twenty-seven patients were older than 65 years of age; they had much more preoperative cardiac (P = 0.00003), respiratory (P = 0.0008), and multiorgan impairment (P = 0.009) than did the control group (age less than 65 yrs). Although overall morbidities (44.4% vs. 19.2%; P = 0.01) and overall septic complication rates (33.3% vs. 12.2%; P = 0.02) were higher in aged patients, no significant differences between the two groups were found in the incidence of major surgical complications (18.5% in aged patients vs. 10.5% in control groups; P = NS), serious septic (sepsis score greater than 10) complications (18.5% vs. 7.0%; P = NS) and hospital mortalities (11.1% vs. 3.5%; P = NS). In older patients the occurrence of multiorgan impairment and malnutrition was significantly related to postoperative complication rates. These results suggest that the degree of organ impairment rather than age is predictive of postoperative difficulty and should be used in assessing preoperative risk.

Describes an approach to the design of cellular mobile units featured by 'instinctive' behavior and forming collectively a 'society' of robots. Each robotic unit has its own 'personality' and 'lives' independently from the others. The behavior of each unit derives from a 'subsumption-like' control structure, which emphasizes the roles of 'innate personality', external stimuli, and communication. An example of implementation of instinctive behavior in a real robotic vehicle is presented, and a possible application of the proposed approach to the practical case of a robot system for collecting objects is illustrated. >

On the basis of their experience in right colonic emergencies, the Authors report two cases of diverticular disease presenting with acute abdomen. Pointing out the difficulty of a correct pre- and intraoperative diagnosis, different surgical procedures are analysed.

A two-dimensional model of the piezoelectric transducer for acoustic imaging applications is described. The single piezoelectric element is described, in the frequency domain, by a 5*5 matrix computed by the two-dimensional piezoelectric plate model. In order to simulate the total array, the same model is used to compute a 4*4 matrix describing the inactive material which usually fills the gap between the elements. To predict the behavior of the overall transducer, an algorithm is developed which, using these two matrices, builds the overall matrix of the array. This algorithm has been numerically checked to verify its results. The model easily takes into account the backing and the matching plates. In order to verify its results, a simple array was built, and the measured electrical impedance was compared with the computed one, yielding good agreement. >

A portable system is developed to monitor physical activity by acquiring and storing data from body-mounted sensors; a handheld PC is used for managing data acquisition and storage, including radio-transmission to a remote host. An application related to the use of a gyro-accelerometric sensor for determining walking distance is discussed.

The authors describe their approach to the design of redundant proximity sensor systems that are capable of extracting geometrical information about the surrounding environment and perceiving other relevant features of the reflecting objects, e.g. colour. Potential applications of the proposed sensorial systems are in the field of robotics and autonomous mobility.

Service robots are machines designed to work not onlyfor human beings (like the industrial robot) butalso with human beings. In addition to challenging technical problems, the application of service robots in real-life situations requires to address intriguing issues concerning their interactions with humans. We are investigating both types of problems with reference to three different case studies and real research projects: a mobile robot system primarily aimed at the assistance of patients in hospitals and institutions (the “URMAD” project); a mobile robot system for the assistance to the disabled and the elderly at home (the “MOVAID” project); and a wheelchair incorporating a robot arm (the “IMMEDIATE” project). The paper discusses the design of the three robotic systems as well as their practical implementation and preliminary experimental results. Finally, the paper addresses recent results which could lead to the implementation of cybernetic prostheses, that is devices which would ultimately allow to achieve real intimate physical symbiosis between human beings and artificial robotic devices.